It is desirable for certain environments such as kitchens, bathrooms, toilets etc. to be deodorised. Air fresheners for concealing or removing undesirable odours are well-known, and are commercially available. Air fresheners often require the intervention of a user (e.g. pressing a button or spraying a canister of deodorant), which can prove unreliable and often present hygiene problems.
To provide a reliable source of deodorant, air fresheners are often set up to emit deodorant according to a predetermined schedule (e.g. using one or more logic circuits incorporating a timer). Timed air fresheners such as these can be adapted to release less deodorant at certain times (at night, for example). However, such systems are not strongly correlated with the frequency in which the environment is used, and cannot adapt quickly to situations where more or less deodorisation may be required. For example, public toilets in entertainment venues require more deodorisation during a pause in the performance or event than during the performance or event itself.
Air freshening systems are known which dispense deodorant in response to an indirect action by a user. These actions are usually mechanical, such as opening a door, lifting a toilet cover or opening a lid of a waste-bin. For example, U.S. Pat. No. 4,625,342 describes an air freshener which is actuated by the movement of a toilet flushing mechanism. An actuator arm in the toilet closes a switch to send an electrical signal to the air freshener. However, none of these systems display the flexibility of the present invention.
US 2004/0223943 describes air fresheners that may comprise a container with a propellant for spraying the contents. Various deodorant compositions and features of the air fresheners are described.
WO 97/31718 discloses an electrostatic spraying device which is solar driven to avoid changing batteries. Several operation modes are described: spraying when the batteries are fully-charged and spraying upon demand when a switch is activated. The switch can be activated manually (e.g. press button), electronically (e.g. field effect transistor) or optically (e.g. interruption of a light beam).
US 2003/0168549 provides an example of an electric dispenser for web material. Many aspects of the dispensing can be controlled by means of an electronic control system, a clock system and several internal sensors for paper position, motor consumption and clock circuits.
U.S. Pat. No. 6,883,787 describes a paper towel dispenser with deodorizer. The drive used to rotate the paper towel is used to drive a fan which passes air through the paper towel roll core and out through a hole in the housing. The roll core contains deodorising material.
There remains a need for an air freshener system which is linked to the frequency in which the environment is used, which can assess situations where more or less deodorisation is required and respond quickly, providing more or less deodorant. It would be advantageous if the air freshener system were powered in a simple fashion, and functioned in a simple way (e.g. without requiring complicated sensors and logic circuits in the air freshener). It would also be advantageous if the air freshener system were integrated with other devices in the same surroundings.